The present disclosure relates to prosthetic heart valves and, more specifically, to prosthetic heart valves having an angled stent frame.
A healthy aortic valve acts as a one-way valve, opening to allow blood to flow out of the left ventricle of the heart, and then closing to prevent blood from flowing back into the heart. Diseased or damaged aortic valves may not close properly and thus allow blood to flow back into the heart. Damage to aortic valves may occur due to congenital defects, the natural aging process, infection or scarring. Diseased or damaged aortic valves sometimes need to be replaced to prevent heart failure. In such cases, collapsible prosthetic heart valves may be used to replace the native aortic valve.
Current collapsible prosthetic heart valve designs may be used in high-risk patients who may need a cardiac valve replacement, but who are not appropriate candidates for conventional open-chest, open-heart surgery. These collapsible and re-expandable prosthetic heart valves can be implanted transapically or percutaneously through the arterial system. One percutaneous delivery method entails introducing a collapsible prosthetic heart valve through a patient's femoral artery. This delivery method is referred to as a transfemoral approach.
With reference to FIGS. 1 and 2, a conventional collapsible prosthetic heart valve 1 typically includes a stent 10 for securing the prosthetic heart valve 1 to the patient's native valve annulus and a valve assembly 20 for controlling blood flow. Valve assembly 20 includes a plurality of leaflets 26 attached inside of stent 10. Stent 10 has a distal end 2, a proximal end 4, a first side 22 and a second side 24. The first side 22 and second side 24 of stent 100 have the same, or a substantially similar, height H4. As seen in FIG. 2, due to the anatomy and acute curvature of the aortic arch A, conventional stent 10 and valve assembly 20 cannot always be aligned with the native valve annulus N. When conventional prosthetic heart valve 1 is deployed near the native aortic valve, stent 10 and valve assembly 20 may be canted toward the descending aorta at the valve annulus N. As a consequence, prosthetic valve leaflets 26 will not be in alignment with the native valve leaflets. The improper positioning of the leaflets 26 with respect to the valve annulus N may adversely affect the functioning of conventional prosthetic heart valve 1. In addition, the orientation of conventional prosthetic heart valve 1 at an oblique angle relative to aortic valve annulus N may exert uneven forces on surrounding tissue, including the mitral valve annulus, or otherwise interfere with the proper function of the mitral valve. In light of the issues described above, improvements to current prosthetic heart valve designs are desirable.